The problem with the company's hosted domain name service, which provides links from sites' domain names to the numbered Internet addresses where data is actually reached, affected only Web sites which had allowed Network Solutions to take over this address-book service for them. The company had recently touted the near-infallibility of its addressing system as a core selling point for new customers.
A representative for the company said a software bug had affected the service in a way that a file containing information needed to direct Web address requests had been truncated, affecting all the company's managed domain services. The problem did not reach the global domain name system (DNS) components that the company also helps operate.
The outage, although resolved in just three hours, illustrates what remains a persistent point of concern about the Internet's infrastructure.
The global DNS, responsibility for which is spread between many companies and servers, does have many fail-safe elements built in. It would be nearly impossible to attack the system in such a way that all Web addresses on the Net were immediately taken down, for example.
But experts say various components of that naming and routing system remain vulnerable. Aon 13 of the most critical, or "root," DNS servers last October prompted about the system's vulnerability, despite the attack's relatively minor effect on ordinary Net surfers.
The Network Solutions issue showed another aspect of DNS vulnerability, crippling customers' businesses for several hours.
Ron Warren, chief information officer for Washington, D.C.-area contractors Mona Electric Group, said his company found itself unable to reach its Net-connected intranet sites, leaving employees on multimillion dollar contracts without the information needed to work on their jobs.
"We were able to work around it for four hours," Warren said. "But if it had gone any longer, we would have been severely impacted."